Your aerial over time suffers a colossal amount of deterioration from the weather particularly in our climate. Roasting one minute freezing wind the next.
Cars in the British climate fair no better whereas a car in a sunny state state in America don’t suffer from rust just mechanical failure,so it isn’t hard to spot a 50 year old car still running around on the streets of los angeles be it rather battered and smoky.
Aerials are made from steel and aluminum materials that our climate loves to get its teeth into. Your TV aerial can withstand a certain amount of weakening on its structure due to rust weakening brackets lash cables etc.
But the extra loading of say even a light breeze can and does prove to much,a gale will definitely expose even the slightest failing in any aspect of your aerials structure,and lo and behold it can and will cause damage to to your roof new car or even yourself if you happen to be in the wrong place at the wrong time.
If your aerial as been up for say more than 5 years it is very likely that the next high wind will bring it down,you might be lucky and just find it laying on your roof or drive or you might not be so fortunate